# encoding=utf8

def digui(n: int) -> int:
    result = 0
    if n == 1 or n == 2:
        return 1
    result = digui(n-1)+digui(n-2)
    return result


print(digui(22))

# 1 1 2 3 5 8 13 21 34 55




# 1 3 9 27